Load indicator



Sept. 10, 1935. E. 1. S|||MEK 2,013,810

LOAD INDICATOR Filed March '7, 1932 3 Sheets-Sheet' 1 E 9\ J az 3l 33 45 I atto! nu,

u Sepi @0,71935- E. J. sHlMEK LOAD INDICATOR Filed March' '7, 1932 3Sheets-Sheet 2 Sept. l0, 1935.

E. J. SHIMEK LOAD INDICATOR Filed March 7, 1952 3 Sheets-Sheet 3 a Ul alw

. L 62 BZ 82 dw gwvmto Patented Sept. `l0, 1935 UNITED STATES PATENTvori-HCE LOAD INDICATOR Edwin J. Shimek, Houston, Tex.

Application Marchi, 1932, Serial No. 597,135

Claims. (Cl. 265-47) 5 or deect a portion of a cable, and loadindicating means responsive to the forces tending to straighten it.These forces vary directly with the angle of deflection of the cable,and so calibration of the indicator is necessarily based on a givenangle.

One of the principal objects of the present invention is to provide newand improved means to keep the angle of deection of the cablesubstantially constant so that the indicator will at all ,timesaccurately indicate varying loads .on the cable.

Conventional deep well drilling vapparatus includes a cable having oneend, known as the dead line, connected to a fixed support. The cable ispassed through a crown block and a traveling block and has its other endwound upon a hoisting drum. The tension in the dead line, caused by adrill stem of a given weight, is therefore dependent upon the number oflines between the crown block and the traveling block. It is customaryto connect a weight indicator to the dead line, the calibration of whichis based on the number of lines between the traveling block andthecrownV block. When the number of lines is reduced or increased, anotherweight indicator must be used, Y

The new and improved load indicator provided by this invention will befound particularly useful for attachment to a dead line to indicate theweight of a drill stem, because it may be quickly and easily adjusted toaccurately give the correct weight of the drill stem when the number oflines between the crown block and traveling block are varied; theadjustment being eected by changing the angle of deection of the cableto compensate for the new mechanical advantage of the pulley assembly,without disturbing the load indicating means.

Other objects will hereinafter appear.

'I'he preferred embodiments of the invention are illustrated by theaccompanying drawings, of which Fig. 1 is a partly sectional elevationof one embodiment of the load indicator applied to `a cable; Fig. 2, asection on the line 2-2 of Fig. 1; Fig.` 3, a somewhat diagrammatic viewof the load indicator applied to deep well drilling apparatus;

Fig. 4, a fragmentary, sectional view of another embodiment of theinvention; Fig. 5, a detail view of another embodiment showing theconnecting means between the body shank and beam; Fig. 6, a detail viewshowing the body shank of Fig. 5; 5 and Fig. 7, a detail view showing'the means to lock the shank and beam of Fig. 5.

Referring to Figs. 1 and 2, the numeral I indicates a beam havingtransversely projecting arms 2 and 3 grooved for the reception of thecable 4. 10 The body 5 may comprise two sections 6 and 1 connected bybolts 8. The inner section 1 of the body has a centrally disposed shank9 projecting through a bore I0 in the beam I and held therein by a nut II. The shank 9 is longitudinally slotted, l5 as indicated at I2, for thereception of the cable 4 and a pin I3, the latter of which preventsrotation of the shank 9 in the bore I0. The beam I hastherein aplurality of spaced openings I4, I5 and I6;and theshank 9 has adjacentthereto 20 openings I1, I8 and I9. As shown clearly by Fig. 2, a pin 20may be passed through the openings I6 and I9. The pin l3,as shown.- hasan opening therein to permit this. The shank 9 may be held in differentpositions in the bore Ill by passing the 25l pin 20 ,through any two ofthe openings I4, I5 and I6, and I1, I8 and I9, for a purpose hereinafterset forth.

Withinthe body 5 is a member 2| having a central lug 22 projecting inthe bore 23 of the 30 -shank 9 into engagement with the cable 4. The

has a diaphragm 26 secured thereto and clamped 35 by the bolts 8 betweenthe sections 6 and 1, whereby a sealed pressure chamber 21 is formed inthe body 5.A The body 5 has an ,outlet port' 28 in which is an outletvalve seat 29 for the outlet valve 30. The outlet valve 38 is connectedto a cylinder 40 3I by threads 32.- vThe cylinder 3| forms a chamber 33.The chambers 33 and 21 are connected by a port 34; and the passage offluid from the chamber 33 to the chamber 21 through the port 34 iscontrolled by a valve 35 normally held upon a seat 45 36 by acompression `spring 31. The valve 35 is rconnected by a pin 38 tc a plug39 carried by the member 2|, and a compression spring 40 may be used toassist the spring 31 in normally keeping the valve 35 closed. 50 Thechamber 33 is supplied with fluid under pressure, such as steam or thelike, by a pipe 4I connected as indicated at 42a (Fig. l) to a supplypipe 42 (Fig. 3). The supply pipe 42 may be connected to a `boiler orother source of supply (not convenient support 44 may be connected by apipe 45 (Fig. 3) to the body 5 at 46(Fig. 1).

i In Fig. 3, which illustrates conventional deep block 48 supported by acrown block 49, the latter of which is stationarily mounted in thederrick, not shown. One end of the cable- 50 is wound upon a hoistingdrum 5|, and the dead line 52 of the cable is connected to a stationarysupport .53. 'I'he load indicator may be applied vto the dead line 52,as shown..

It will be understood that this invention may be used wherever means aredescribed to indicate varying loads on a flexible member under tension.The invention will bey found particularly useful, however, in connectionwith deep well drilling apparatus, as follows:

In deep well drilling, it is'essential that certain pressures be appliedto drill bits to insure efcient cutting of certain formations. Theapplication Y of greater pressures must be prevented to avoid damage tothe drilling apparatus.

The preure on a drill bit is afforded by a heavy drill stem 'whichcomprises a plurality of pipe sections, to the lowermost of which thedrill bit is attached. The weight of a lengthy drill stem imparts apressure greater than can be used advantageously or even safely, underusual conditions, and it is now customary for the driller to repeatedlyascertain the .weight of the stem by means of weight indicators and thenso adjust the stem supporting mechanism thatthe excessive part of thestem weight is thereby supported.'

In Fig.`3, the dead line 521 is in the place of the cable 4 of Fig. l.The tension in the dead line 52 will be dependent upon the weight ofthedrill stem 41. As the weight of the drill stem 41 is placed upon thetraveling block 48, the dead line 52 will exert two transverse forces inone direction against the arms 2 and 3 of the beam I, and one transverseforce inthe other direction against the lug 22 of the member 2 I;whereby the member 2| will be forced a verysllght distance in thechamber 21. Now as the normally closed inlet valve 35 is carried by themember 2|, and the inlet valve seat 36 is held by the cylinder 3|, the

outlet valve 30, and theoutlet valve seat 28, the inlet valve 35 willbe.opened, so that fluid under pressure from the inlet chamber 33thereupon enters the pressure chamber 21 to immediately increase thepressure ofthe fluid in chamber- 21 and prevent further inward movementof the member 2|. It will be understood that the pressure of the fluidin the supply pipe 42, pipe 4| and chamber 33 is suilicient to create apressure in the chamber 21 that will prevent such further inwardmovement of the diaphragm even when there is on the dead line 52 amaximum load. And so, the member h2| is never permitted to move inwardlymore than a very short distance.

Now when the load of the drill stem 41 on the traveling block 48 isdecreased, the tension in the dead line 52 will be decreased, so thatthe fluid under pressure in the chamber 21 will force the member 2|outwardly. When the member 2| isl moved outwardly only a very shortdistance, the

exhaust valve 30 is opened because it is .carried shown) A pressuregauge. mounted on some the inward and outward movement of the member 2|is very` slight, the lug 22 .of the member, and the arms 2 and 3 of thebeam will remain in substantially the same positions with respect toeach other as the load varies, so thatfthe angle 5 of deilectio'n of thecable may be regarded as remaining practically constant. 'This isimportant because the pressure in the chamber 21 is dependent ,not onlyon the load on the cable but also on the angle of deilection of thecable; and so a cer- 1o tain load on the cable invariably creates acertain pressure in the chamber 21 and the calibrated pressure'gauge 43accurately indicates the varying weights of the drill stem.

' It may be added that if some of the liquid es- 15 capes from thepressure chamber of a conventional weight indieator'or if some4 gas' ispresent 0r if the temperature of the liquid in the pressure chamber isincreased or reduced appreciably, the angle of deflection of the cableis changed; 20 and, as the calibration of the pressure indicator isnecessarily based on a certain angle of deflection, it cannot thereafterindicate the correct load on the cable. As above stated, this inventionprovides new and improved means to keep the angle 25 of deflectionsubstantially constant, to cause accurate indications.

Referring now to Fig. 3, it will be apparent that the upward pull on thedead line 52 would be dependent not only on the downward pull by the 30drill stem 41 on the traveling block 48 but also on the number of linesbetween the traveling block 48 and crown block 48. In the apparatusshown, the upward pull on the dead line 5 2 will be onefourth of thedownward pull on the traveling 35 block 48. the mechanical advantagebeing 4 to 1. 'I'his will create a certain pressure in the chamber 21and the pressure gauge 43 will indicate a certain weight. When themechanical advantage of the pulleys is changed to 6 to l, or 8to 1, 40byadding lines. between the traveling block 48 and 48, the,pull on thedead line 52 will vbe proportionately less for the same stem load andthe pressure in the chamber 21 will therefore be less so that the gauge43 will not indicate the correct 45 weightof the drill stem 41. Now, asabove stated, the pressure of the uid in the chamber 21 is dependent.notA only on the tension in the cable but also upon the angle ofdeection of the cable, and this angle of deflection is fixed by holding50 the arms 2 and 3 of the beam and the lug 22 of the member 2| inpredetermined positions with respect to each other, /by placing the pin28 in openings in the beam and shank '8. To make the gauge 43 indicatethe same weight 55 when the mecha. ical advantage of the pulleys isincreased, the angle of deflection of the cable is increased by removingthe pin 20 from the openings |6 in beam `and the openings I8 in shank 9,moving the shank 8 further in the bore I8, and 60 then placing 4the pin28 in the openingsi 5 and |8, or |4 and |1. Although the load on thedead line 52 is less because of the mechanical advantage of the pulleys,the dead line exerts a greater force on the diaphragm when the angle ofde- 65 j ection is increased, so that the pressure in the chamber 21`isthe same as it was when the load on the dead line was greater. Andtherefore the pressure gauge 43 indicates thevsame weight it indicatedbefore the mechanical advantage of 70 the pulleys was changed.

In view of the foregoing, it is unnecessary to use any additionalapparatus whenv the mechanical advantage ofv the pulleys is changed. The

pressure gauge and all other'parts remain in 75 ful Lof

place.l It is necessary only to change the angle of deflection of thecable by placing the pin 2l) in diierent holes.

Fig. 4 illustrates another embodiment. In this embodiment, the member 60may be mounted in the body 6| (as suggested by Fig. 1) and provided witha lug 62 to engage thecable 4 extending through the slot 63 in shank 64.

A diaphragmv 65 is secured to the member 6| by bolts 66 and has means B1to which the pressure gauge 43 (Fig. 3) may be connected; an exhaustopening 68; and an inletopening 69 to which the inlet pipe 42 may beconnected. The base 65 has a central cylinder 10 projecting into thepressure chamber 1|. A'plunger 12 is movable in the cylinder 10 and isheld against the member 60 by compression springs 13 and 14.

The spring 13 bears against the base 65 and the plug 15 of the plunger12; and the spring 14 bears against the inlet valve 16 and the plunger i12. The inlet valve 16 is adapted to fit a seat formed by the plug 15,and is connected by a rod 11 with the outlet valve 18. The outlet valve18 is adapted to engage a seat formed by a plug 19 in the base 65.Connected to the plunger 12 at 80 and communicating with its inlet chamfber 8| is apipe'82 connected as indicated at 83 to the base 65, and towhich the supply pipe 42 may be connected at 69.

- When the member 60 is moved a slight distance inwardly in the chamber1|, it will move the plunger 12 to move the inlet valve seat away fromthe inlet valve 16, whereupon fluid under .pressure will escape from thepressure chamber 8|, through the plug 15, between the plunger 12 andcylinder 10 into the chamber 1| to prevent further inward movement ofthe member 60. Fluid under pressure escaping from the chamber 8| isreplaced by fluid entering through supply pipe 42 and pipe 82. The pipe821s coiled about the cylinder 10 so that it will be flexible and notinterfere with the movement of theplunger 12 in the cylinder 10.

The fluid under pressure in the chamber 1| will move the member r|50outwardly a slight distance when the load on the cable is reduced, andthe springs 13 and 14 will cause the plunger 12 to follow the member 60so that the outlet valve 1B will be opened, and a portion of the fluidin the chamber 1| will be permitted to escape from the chamber 1|,between the cylinder 10 and Y plunger 12 through the plug 19 and out ofexhaust openings 68, to prevent further outward movement of the member.

As the pressure operated elements of the embodiment just described arecarried by the base 65 they may be readily removed and replaced as aunit.

Figs. 5, 6 and 7 illustrate another embodiment of means whereby theangle of deflection of the cable may be changed to compensate for themechanical'advantage of pulley assemblies or the like. The elements Aofthis embodiment correspond to the elements of the FE. 1 embodiment, asindicated by the numerals. The beam is indicated at the adjacent sectionof the body at |01; and the shank of the body at |09. The shank |09 isheld in the bore ||0 of the body by a nut The shank |09 is marked asindicated' at |90 and the beam has an opening |9| and adjacent thereto amark |92. The marks |90 and |92 are so disposed that when mark |92 iscoincident with one of the marks |90, a diaphragm lug corresponding tothe lug 22 of Fig. 1 is in a predetermined position with respect to beamarms corresponding to the s 2" and 3 shown by Fig. 1 so that the angl ofdeflection of the cable is necessarily a predetermined number ofdegrees.

-The screw is rotated to cause one of the marks |90 to coincide with themark |92 to x the angle of deflection of the cable; and a set' screw |93carried by an arm |94 integral with beam |0| is then screwed inwardlyinto engagement with the nut to lock the parts in place.

It is to be understood that this invention is not limited to thepreferred embodiments herein disclosed. Various .changes may be madewithin the scope of the following claims.

I claim:

1. A tension indicator adapted to be attached to the dead end line of awell drilling rig, comprising a beam adapted to engage the dead end lineat two spaced points, pressure operated means for deecting said linebetween said points, and for maintaining said deflection substantiallyconstant, pressure responsive means indicating the force required tomaintain said deflection and means for adjusting the degree of suchdellection in accordance with the mechanical advantage obtained by theload support of said rig.` Y

2. A load indicator adapted to be attached to the dead end line of awell drilling rig, comprising a beam adapted to engage the dead end lineat two spaced points, pressure operated means'for deflecting said linebetween said points, saidpressure operated means serving to maintainsaid deilection substantially constant irrespective of the tension of,said line and means for adjusting the angle of deflection in accordancewith the mechanical advantage obtained by the load support pulleys ofsaid rig whereby a given calibration of said pressure responsive meansmay be used with rings of different mechanical advantage.

3. A tension indicator for showing the tension 40 exerted on a flexiblecable comprising a -beam adapted to engage the cable at two spacedpoints, a

diaphragm chamber having a diaphragm therein, said diaphragm having-'amember secured thereto and adapted to engage the cable intermediate thepoints of engagement of said beam, fluid pressure means for exertingpressure upon said diaphragm to deflect the portion of the cableintermediate the pointsof engagement of said beam, and for maintainingthe angle of deflection of said cable substantially constantirrespective of the tension thereof, and means for adjustably connectingthe diaphragm chamber to said beam whereby the said angle of deflectionmay be varied in accordance with the mechanical advantage of theapparatus with which the indicator may be used.

4. A load indicator adapted to be attached to the dead end line of awell drilling rig comprising a beam adapted to engage said line at apair of spaced points, a diaphragm chamber having a diaphragm therein,said diaphragm having a member adapted to engage the cable at a pointintermediate the points of engagement of said beam, said diaphragmchamber having a bifurcated member passing into a bore in said beam,means for securing said bifurcated member within said beam in aplurality of different positions whereby the angle of deflection of thecable may be varably set, and pressure responsive means for maintainingthe angle of deflection of the cable substantially constant at theangleset irrespective of the tension thereon.

5. A load indicator adapted to be attachedI to the dead end line of awell drilling rig comprising 10 tially constant, said means forconnecting said diaphragm chamber with said beam comprising a' pluralityoi' apertures located in said beam and a plurality of correspondingapertures within the portion oi' said diaphragm chamber adjacent saidbeam. and a pin for locking said members in engagement whereby the angleot deection o! said cable may be varied in accordance with themechanical advantage oi' the particular well drilling rig with which theindicator is used.

EDWIN J. SHIMIEK. n

